Trench shoring, shuttering and sheeting system

ABSTRACT

Trench shuttering system with a pair of upright posts spaced apart along opposite sides of a trench, and horizontally extending wall elements received between the posts and the trench wall. Each of the wall elements comprises a pair of parallel and relatively slidable members overlapping one another and releasably secured together by manually operable clamping means at the overlapping junction.

United States Patent 1 [111 3,727,413 Christen [451' Apr. 17, 1973 TRENCH SHORING, SHUTTERING 3,186,177 6/1965 Kannenberg ..6l/4| A ND SHEE ING S M 3,230,720 1/1966 Bennett ..61/41 A [76] Inventor: 2: s gifg Primary Examiner-Dennis L. Taylor Attorney-Karl F. Ross [22] Filed: Aug. 10, 1971 Appl. No.: 170,553

[30] Foreign Application Priority Data Aug. 13, 1970 Switzerland ..l2305/7O [52] US. Cl. ..6l/4l A, 61/63 [51] Int. Cl. ..E21d 5/12 [58] Field of Search ..6l/41A,41,47,

[56] References Cited UNITED STATES PATENTS 1/1907 Fitzgerald ..61/41 A [5 7] ABSTRACT Trench shuttering system with a pair of upright posts spaced apart along opposite sides of a trench, and horizontally extending wall elements received between the posts and the trench wall. Each of the wall elements comprises a pair of parallel and relatively slidable members overlapping one another and releasably secured together by manually operable clamping means at the overlapping junction.

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CK rl 9 Attorney TRENCH SHORING, SHU'I'IERING AND SHEETING SYSTEM Up to now trench shoring has been accomplished simply by means of horizontal boards braced with vertical scantlings and jacks, or else by means of vertical planks or steel shuttering braced with timber props, girders to German DIN standards, etc.

More elaborate shoring systems are awkward and are therefore'not employed on a wide scale.

The shoring systems known heretofore are open to the objection that men working in the trench need ladders to get in or out, so that a sure escape route is not guaranteed in the event of danger.

The present invention relates to an improved trench shoring system which overcomes these disadvantages.

According to the invention this is achieved by having horizontal shoring elements detachably arranged one above the other between two vertical props, on each wall of the trench. Each shoring element comprises two parts relatively displaceable lengthwise and joined friction-tight at the points where they overlap. The top longitudinal edge of each lower element is substantially level with the bottom longitudinal edge of the next element above it, the bottom longitudinal edges of the elements being set back in relation to the top edges when looking at them from inside the trench, so that the top longitudinal edges of the shoring elements projecting towards the inside of the trench provide handgrips and footholds for climbing into and out thereof.

Contrasted with the conventional shoring techniques, the system of the present invention has the advantage that the steps formed by the shoring enable it to be used as a ladder extending the full length of the trench or shoring.

The principal advantage of the design in accordance with the invention is, however, seen in that the longitudinal spacing between the vertical props does not have to be maintained exacty. Instead it may be varied, allowing speedy and convenient erection of the shoring. Another particular advantage is that shoring elements may be fitted or taken out separately. All these features enable the length of the trench to be subdivided rationally and permit the shoring to be conveniently adapted to local obstacles, such as service pipes, cables, large stones, shafts, etc.

The accompanying drawing shows by way of example an preferred form of embodiment of the invention, and wherein:

FIG. 1 represents a vertical cross section of the shoring system erected in a deep trench;

FIG. 2 is a vertical section taken along the line IIII of FIG. 1 with an elevation of one side of the trench shoring, on a larger scale;

FIG. 3 shows in plan view a fragmentary part of the trench shoring system;

.FIG. 4 is a sectional view of a shoring element taken along the line IVIV of FIG. 3, on an enlarged scale;

FIG. 5 is a sectional view of the joint in a two-piece shoring element extending between two vertical props;

FIG. 6 is a top view of a joint fixing clamp on an enlarged scale, in the direction of the arrow VI of FIGS;

FIG. 7 shows a fragmentary view of a vertical prop with two adjacent shoring elements hung therein;

FIG. 8 shows a sectional view of the shoring system erected in a less deep trench.

Referring to the annexed drawing, the trench shoring system illustrated in FIG. 1 to 3 has vertical props designated 1 of H profile arranged at intervals of, say, 3 meters. At the top of the prop, in the web of it's profile, is a hole 2 (FIG. 2) for pulling out the prop. The bottom ends 3 of the props slope in toward the side of the trench G, so as to force the props against the trench wall on being driven in. In the two flanges of the vertical prop 1, on the sides of the flange facing into the trench, are holes 4 at regular intervals corresponding to the height of a shoring element. The standardized shoring elements 5 are profiles of sheet steel or light metal, manufactured with a cross section calculated to resist bending (FIGS.4 and 5). The two longitudinal edges of the shoring elements 5 have rolled rims 6, into which projecting fixing pins 7 or 7' are inserted and secured at the end adjacent to the vertical prop. On assembling the shoring elements 5, the fixing pins 7 in the top Ion gitudinal edges of the profiles engage the holes 4 of the vertical props 1. Ifthe distance between vertical props in three meters for example, with shoring elements having a length of about two meters, it will be necessary to use two elements to bridge this interval. The elements overlap, and are held together where they overlap by means of fixing clamps 8. In the form shown, FIG. 3, the elements 5 are held together at the overlapping joint by means of two clamps 8. These clamps have each a locking device 9 (FIGS). The clamps are of narrow rectangular shape and accommodate two shoring elements 5 lying one above the other together with the locking device 9. The latter includes a pivot pin 11 protruding through the top and bottom of clamp 8 at the holes 10, and inside the clamp the pin carries a pressing ledge 12 acting as an eccentric. The top end of the pin projecting above the clamp 8 has a square shank 13. The locking device 9 is operated with a key (not shown) having a square hole which is fitted over the square section 13. By means of this key the pin 1 l is turned so as to cause the eccentric ledge 12 to press against the profile elements, locking these friction-tight with each other. The two-piece shoring profiles, fixed lengthwise by contact pressure at the joint, are thus secured in their engagement with the holes-4 in the props l. The pins 7' fixed to the bottom longitudinal edges of the shoring elements rest against the edges of the vertical prop facing the wall of the trench, as shown in FIGS. 1 and 4. By having the shoring elements 5 with the vertical props 1 assembled in this way, steps 14, (FIGS. 1 and 8) are formed by the top edges of the elements 5 and the set-back edges of the elements above, so that the shoring along both walls can be used for climbing in and out over the full length of the trench.

The vertical props 1 are arranged in pairs facing each other, and are braced by jacks 15 whose ends rest on the pins 7 inserted in the holes 4 of the props l and are prevented from slipping out sideways by the profile flanges thereof. Boards 16 laid along the longitudinal edges of the trench and fixed to the props I prevent soil or stones dropping in.

Procedure for erecting the shoring is as follows:

For deep trenches as in FIG. 8, to 3 the vertical props 1 are driven in direction and depth by a rammer, as lined out, alternately excavating the trench further and driving the vertical props l deeper again.

For shallower trenches as in FIG. 8, excavation to the depth allowed by the regulations in accomplished with a backhoe, without bracing or shoring, whereupon the vertical props are driven in to the required depth and the bracing jacks 15 applied.

Upon excavating the trench in accordance with FIGS. 1 to 3, the opposite pairs of vertical props l, disposed in spaced relation of, say, three meters, are braced with the jacks 15.

When mounting the shoring elements between two vertical props, two clamps 8 are pushed onto one of the two shoring elements 5 to be arranged at the same height. This element is then fitted into the corresponding hole 4 of one vertical prop l with its top fixing pin 7, as shown in FIGS. 3 and 4, bringing the element at the same time into an inclined position relative to the trench wall with he bottom pin 7' resting on the edge of the vertical prop l facing the trench wall. The second shoring element or profile 5 is pushed with its pinless end into the clamps 8 mounted on the pinless element of the first element, so that the two profiles lie flat against each other as shown in FIG. 5 and overlap. At the same time the fixing pin 7 in the top edge of the second element is inserted in the hole 4 of the next vertical prop l at the desired height, making sure that the bottom pin 7' rests on the edge of the prop facing the trench wall. The clamps 8 are then shifted up to about 10 cm from the inner ends of the profiles, as shown in FIG. 3. With the two shoring elements thus adjusted to the appropriate overall length, the locking device 9 FIG. 5) of the two clamps 8 is turned into its locked position by means of the appropriate key so as to join the elements friction-tight over their overlapping' lengths. This joint fixes the combined length of the two shoring elements to match the spacing of the vertical props.

By fixing the shoring elements at an angle, the top longitudinal edges are made to project beyond the bottom longitudinal edges so as to form steps 14 that extend the full length of both trench walls, enabling the workers to climb in and providing a means of escape in the event of danger.

Dismantling of the shoring elements is effected analogously in the reverse sense.

The shoring elements are standardized, enabling space to be saved during transportation and storage on the site. Owing to their profile it is possible to keep their weight low.

The simple design means straightforward handling by unskilled labor when erecting and dismantling the elements. In the erected state there are no parts of the elements protruding into the trench space.

wall elements horizontal]? running between the respective post and the face 0 the trench at the respective side, each of said elements comprising a pair of parallel, overlapping and relatively longitudinally shiftable members, and means for releasably securing the members of each element together at the overlapping portions thereof.

2. The trench-shuttering system defined in claim 1 wherein a pair of such vertical posts are provided in horizontally spaced relationship along each side of the trench, said elements each being provided at its end with a respective pin receivable in one of the posts of each pair whereby the members of each element span the respective pair of posts, said pins retaining said elements in an inwardly upwardly inclined relation relative to said posts to form hand grips and footholds enabling the climbing into and out of the trench.

3. The trench-shuttering system defined in claim 2 wherein said posts are H profiles and said means for propping said posts on opposite sides of said trench apart includes jacks bearing upon pins of said'elements and retained against dislodgrnent between the flanges of the H profile.

4. The trench-shuttering system defined in claim 3, further comprising means on said posts for urging lower edges of said elements toward the respective face of the trench upon downward insertion of said elements between the posts of each pair.

5. The trench-shuttering system defined in claim 2 wherein said elements are sheet metal profiles having rolled rims along their longitudinal edges receiving said pins.

6. The trench-shuttering system defined in claim 5 wherein said means for releasably securing said members together comprises a clamp interconnecting the overlapping portions of said members, an eccentric locking device received in said clamp and a pin having a non-circular shank projecting from said clamp for operating said device. 

1. A trench-shuttering system comprising a pair of spaced apart vertical posts positionable along opposite sides of a trench; means for propping said posts apart; and respective wall structures received between each of said posts and the respective side of the trench, each of said wall structures comprising a multiplicity of substantially laterally adjacent longitudinally extending wall elements horizontally running between the respective post and the face of the trench at the respective side, each of said elements comprising a pair of parallel, overlapping and relatively longitudinally shiftable members, and means for releasably securing the members of each element together at the overlapping portions thereof.
 2. The trench-shuttering system defined in claim 1 wherein a pair of such vertical posts are provided in horizontally spaced relationship along each side of the trench, said elements each being provided at its end with a respective pin receivable in one of the posts of each pair whereby the members of each element span the respective pair of posts, said pins retaining said elements in an inwardly upwardly inclined relation relative to said posts to form hand grips and footholds enabling the climbing into and out of the trench.
 3. The trench-shuttering system defined in claim 2 wherein said posts are H profiles and said means for propping said posts on opposite sides of said trench apart includes jacks bearing upon pins of said elements and retained against dislodgment between the flanGes of the H profile.
 4. The trench-shuttering system defined in claim 3, further comprising means on said posts for urging lower edges of said elements toward the respective face of the trench upon downward insertion of said elements between the posts of each pair.
 5. The trench-shuttering system defined in claim 2 wherein said elements are sheet metal profiles having rolled rims along their longitudinal edges receiving said pins.
 6. The trench-shuttering system defined in claim 5 wherein said means for releasably securing said members together comprises a clamp interconnecting the overlapping portions of said members, an eccentric locking device received in said clamp and a pin having a non-circular shank projecting from said clamp for operating said device. 